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61.
杨崇豪 《华北水利水电学院学报(社会科学版)》2002,18(4):38-40
国家卫生部2001年6月7日颁布的《生活饮用水水质卫生规范》和国民及政府对环境保护的要求标准,给进入21世纪的中国水务工程市场带来了喜人的市场机遇,但是也存在着巨大的融资困难。BOT模式是解决融资困难的一条极其有效的途径。内资民营企业的加入将成为中国BOT水务项目的主体。通过实例对BOT水务工程存在的风险以及规避方法进行了初步探讨。 相似文献
62.
李伟 《郑州航空工业管理学院学报(社会科学版)》2006,25(3):58-60
互联网的崛起为人们的日常生活、学习和工作带来了诸多便利,然而,作为一种全新的信息技术范式,互联网也给人类社会生活带来了许多新的风险。文章分析和论述了网络风险的各种表现形式、网络风险的实质以及网络风险产生的根源,以期为网络风险管理提供借鉴。 相似文献
63.
李志宏 《厦门大学学报(哲学社会科学版)》2006,3(1):118-124
新实践美学和实践美学的审美发生理论都是以哲学方法取代科学实证方法,消解了哲学作为方法论的指导意义;都违反了辩证唯物主义立场,以意识性的哲学概念为物质性的审美发生的原点;都将现代人类的知觉混同于动物的知觉,不能解释为审美所必需的形式知觉力的发生和作用.认知科学美学认为:审美发生要以人类智能的高水平发展为物质基础;以现代人类特有的形式知觉力的形成为决定性的主体条件.审美情感、审美价值、审美属性都依据这一条件而发生. 相似文献
64.
William S. Pease 《Risk analysis》1992,12(2):253-265
The extent of carcinogen regulation under existing U.S. environmental statutes is assessed by developing measures of the scope and stringency of regulation. While concern about cancer risk has played an important political role in obtaining support for pollution control programs, it has not provided the predominant rationale for most regulatory actions taken to date. Less than 20% of all standards established to limit concentrations of chemicals in various media address carcinogens. Restrictions on chemical use are more frequently based on concerns about noncancer human health or ecological effects. Of the chemicals in commercial use which have been identified as potential human carcinogens on the basis of rodent bioassays, only a small proportion are regulated. There is an inverse relationship between the scope of regulatory coverage and the stringency of regulatory requirements: the largest percentages of identified carcinogens are affected by the least stringent requirements, such as information disclosure. Standards based on de minimis cancer risk levels have been established for only 10% of identified carcinogens and are restricted to one medium: water. Complete bans on use have affected very few chemicals. The general role that carcinogenicity now plays in the regulatory process is not dramatically different from that of other adverse human health effects: if a substance is identified as a hazard, it may eventually be subject to economically achievable and technically feasible restrictions. 相似文献
65.
Peter J. Robinson 《Risk analysis》1992,12(1):139-148
Because of the inherent complexity of biological systems, there is often a choice between a number of apparently equally applicable physiologically based models to describe uptake and metabolism processes in toxicology or risk assessment. These models may fit the particular data sets of interest equally well, but may give quite different parameter estimates or predictions under different (extrapolated) conditions. Such competing models can be discriminated by a number of methods, including potential refutation by means of strategic experiments, and their ability to suitably incorporate all relevant physiological processes. For illustration, three currently used models for steady-state hepatic elimination--the venous equilibration model, the parallel tube model, and the distributed sinusoidal perfusion model--are reviewed and compared with particular reference to their application in the area of risk assessment. The ability of each of the models to describe and incorporate such physiological processes as protein binding, precursor-metabolite relations and hepatic zones of elimination, capillary recruitment, capillary heterogeneity, and intrahepatic shunting is discussed. Differences between the models in hepatic parameter estimation, extrapolation to different conditions, and interspecies scaling are discussed, and criteria for choosing one model over the others are presented. In this case, the distributed model provides the most general framework for describing physiological processes taking place in the liver, and has so far not been experimentally refuted, as have the other two models. These simpler models may, however, provide useful bounds on parameter estimates and on extrapolations and risk assessments. 相似文献
66.
龙宏 《重庆大学学报(社会科学版)》2002,8(3):47-48,56
美是真理的光辉 ,美感直觉不仅对于艺术家 ,而且对于科学家都同样重要。事实上 ,对自然界中简洁、和谐、秩序美的坚信与追求曾无数次帮助科学家拨开遮挡真理之光的乌云 相似文献
67.
本文阐述了期货市场法律规范的基本原则和主要功能,介绍了我国期货市场的近期发展与法规现状,并对我国期贷市场法律规范的基本原则与体系设置作了探讨。 相似文献
68.
A survey was conducted of approximately 200 Asian Indian Americans and 200 other residents of New Jersey in order to understand the risk management priorities that they want government to have. We found that Asian Indian Americans, especially younger women, focused on personal/family risks, such as alcohol and drug abuse, sexual abuse, and domestic violence. The New Jersey comparison group, in contrast, placed war/terrorism and loss of health care services and insurance at the top of their priorities for government. These results suggest stressful acculturation-related issues within the Asian Indian community. Both populations want more risk management from government than they believe government is currently providing. Respondents who wanted more from government tended to dread the risk, be fearful of the consequences, trust government, and have a feeling of personal efficacy. Within the Asian Indian American sample, wide variations were observed by language spoken at home and religious affiliation. Notably, Muslims and Hindi language speakers tended not to trust government and hence wanted less government involvement. This study supports our call for studies of recent migrant populations and Johnson's for testing ethnic identity and acculturation as factors in risk judgments. 相似文献
69.
Xiaomo Jiang 《Journal of applied statistics》2008,35(1):49-65
Multivariate model validation is a complex decision-making problem involving comparison of multiple correlated quantities, based upon the available information and prior knowledge. This paper presents a Bayesian risk-based decision method for validation assessment of multivariate predictive models under uncertainty. A generalized likelihood ratio is derived as a quantitative validation metric based on Bayes’ theorem and Gaussian distribution assumption of errors between validation data and model prediction. The multivariate model is then assessed based on the comparison of the likelihood ratio with a Bayesian decision threshold, a function of the decision costs and prior of each hypothesis. The probability density function of the likelihood ratio is constructed using the statistics of multiple response quantities and Monte Carlo simulation. The proposed methodology is implemented in the validation of a transient heat conduction model, using a multivariate data set from experiments. The Bayesian methodology provides a quantitative approach to facilitate rational decisions in multivariate model assessment under uncertainty. 相似文献
70.
A quantitative criterion for ranking the different scenarios of nuclear and radiological terrorism has been developed. The aim of the model is not to predict terroristic events but only to indicate which scenario has the higher utility from the point of view of a terroristic organization in terms of balance between factors favoring and discouraging the attack, respectively. All these factors were quantified according to a scoring system that takes into account the logarithmic relationship between perceptions and stimuli. The criterion was applied to several scenarios, each of which was modeled in a simple but not trivial way in order to estimate the expected damage in terms of probable life losses from both radiative and nonradiative effects. The outcome from the ranking method indicates that the attractive scenario appears to be the detonation of a low yield improvised nuclear device in the metropolitan area of a major city. 相似文献